How the Lights Stay On · The Order of Operations

The Order of Operations, part 3

The reason solar comes here, not first, is that doing it first means oversizing the system for a house that is wasting energy. You end up paying for a 10-kilowatt system to power a house that, if properly weatherized and electrified efficiently, would have only needed a 6-kilowatt system. The extra cost is real, and it is money you could have spent on the steps that actually reduce demand.

If you were going to buy a car anyway, get an electric one.

The carbon math on EVs has shifted decisively in the last five years. Almost everywhere in the United States, an EV produces less lifetime carbon than a gasoline car, even accounting for the emissions from manufacturing the battery. As the grid gets cleaner (Chapter 10, Chapter 11), the gap grows.

The reason “if you were going to buy a car anyway” matters is that the carbon and money cost of replacing a perfectly good gasoline car with an EV is much higher than the savings. The right time to switch is when your current car needs to be replaced for normal reasons — age, mileage, accident, growing family.

A modern EV in 2026 costs $30,000 to $60,000, with federal and state credits available for many models. The total cost of ownership over ten years, including fuel and maintenance, is usually lower than a gasoline car of similar size.

An EV charging at home will add roughly 3,000 to 4,000 kilowatt-hours to your annual electricity use — enough to be noticeable on your bill but typically less than a heat pump for a similar-sized house. The same panel-upgrade concerns from Chapter 5 may apply.

Home batteries come last. We talked about this in Chapter 7, but it bears repeating in the context of an order-of-operations list.

A home battery makes sense if:

• You live somewhere with frequent outages.

• Your state has a time-of-use rate structure that pays well for storing solar.

• You have already done the other steps and have money left to spend.

A home battery does not make sense if:

• Your goal is purely to reduce your bill in a state with simple rate structures.

• You have not yet electrified your heating, water, or stove.

• You do not have rooftop solar yet (the battery is less useful without it).

The battery is the optional final step. Some households should never buy one. Others should buy one only after they have done everything else.

So why does the order matter so much?

It matters because the cheapest carbon reduction is, almost always, the one nobody can see. Insulation does not look like anything from the street. A heat pump is a beige box behind the house. A heat pump water heater is a slightly taller cylinder in the basement.

The biggest impact you can make on your home’s energy use will be invisible to everyone except your bank account and your electric meter.

This is the deeper lesson of this chapter, and one worth carrying past it. Many of the most important decisions in clean energy are about invisible things. The transmission line that does not get built. The transformer that gets upgraded. The insulation that gets added to a wall. The signal that nudges a thousand thermostats. These are the unglamorous moves that, in aggregate, decarbonize the world.

The solar panels on the roof get the attention. The wires in the wall do the work.

A note on incentives, which keep changing.

The Inflation Reduction Act of 2022 created the most substantial federal clean-energy incentive program in American history. It included tax credits and direct rebates for heat pumps, heat pump water heaters, insulation, weatherization, induction stoves, electric vehicles, rooftop solar, and home batteries.

The Trump administration, returning to office in 2025, has been working to roll back parts of the IRA. The full status of these programs as of 2026 is uncertain. Some tax credits remain. Some rebates have been suspended or restructured. State-level incentives continue to vary widely.

The practical implication: if you or your family is thinking about home electrification, check the current programs in your state and at the federal level before making big decisions. What was true when this book was written may not be true when you read it. The order of operations does not change with incentives. The math of which step pays back fastest can.

If federal incentives are reduced, the order of operations matters even more. Without subsidies, the cheapest-step-first logic becomes the only honest way to spend a household’s clean-energy budget.

This chapter has been more practical than most. Less about the big invisible machines from earlier chapters, more about the choices a family might make over the next ten years.

The reason this practical chapter belongs in a book about the grid is that the grid is not just a thing that happens to you. It is increasingly a thing you are part of.

Every American home is, on the day this book is published, either an actively-participating node on the smart grid (smart meter, heat pump, solar, battery, EV) or a passive consumer of last-century electricity (gas furnace, gas water heater, old wiring, no solar). Most homes are somewhere in the middle.

The choice of where on this spectrum to be is partly economic, partly philosophical, partly about what your priorities are. There is no single right answer.

But if you are going to participate — if you have decided that electrification matters, that climate matters, that bill savings matter — then doing the steps in the right order will get you further per dollar than doing them in the wrong order.

If you are not yet a homeowner, this chapter is for the future you — the one who will be making these decisions in ten or fifteen years. The world will look different by then. The order of operations probably will not.

The most important things are often invisible. Start there.

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